Sunday Under Three Heads seems at first to be one of Dickens's delightful urban sketches. His subject, at least in the first chapter, is simply the different types of people one meets on a typical Sunday morning walk. But in the second chapter, he describes what Sunday morning would look like if the Christian ""fanatics"" in Parliament had been able to pass a recent bill changing the Sabbath trade laws. In the third chapter he discusses what he thinks life on Sunday ought ideally to be like.